Evaluation of the physicochemical properties and quality of the adhesive interface of Bio Root Flow and Bio Root RCS endodontic sealers.

• Grant number: 24/03732-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: October 01, 2024
• End date: September 30, 2025
• Field of knowledge: Health Sciences - Dentistry - Endodontics
• Principal Investigator: Fabiane Carneiro Lopes Olhê
• Grantee: Dione Tavares Reis
• Host Institution: Faculdade de Odontologia de Ribeirão Preto (FORP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

The aim of the present study is to evaluate the physicochemical properties, bond strength, failure pattern, and quality of the adhesive interface formed between the root dentin of Bio Root Flow (Septodont) and Bio Root RCS (Septodont), compared to AH Plus (Denstplay Sirona) gold standard resin based sealer. The study will assess the setting time, dimensional change, solubility, radiopacity, and flow properties of the cements, following ANSI/ADA Specification No. 57 for root canal sealers. To determine the setting time, cylindrical molds (5x2 mm) filled with the cements will be used, and after 150 seconds, the models will be tested with a Gillmore needle (100g) until no marks are left on the surface. For the dimensional change test, 5 cylindrical specimens (3.58 x 3.0 mm) for each tested cement will be obtained, measured with a digital caliper before and after being immersed in 2.24 mL of deionized distilled water for 30 days. For solubility analysis, 10 cylindrical specimens measuring 7.75 x 1.5 mm will be obtained, weighed, and suspended by nylon thread in containers containing 7.5 mL of deionized distilled water. After 7 days, the samples will be rinsed and placed in a desiccator for 24 hours, then weighed again. As a complement to the solubility test, the solutions in which the samples will be immersed for 7 days will be analyzed by atomic absorption spectrophotometry. For radiopacity, acrylic plates with perforations (5 x 1 mm) filled with cement will be fabricated and radiographed alongside a standardized aluminum step wedge with a focus-object distance of 30 cm and exposure of 0.2 s. Radiographic density will be determined using Digora for Windows 1.51. To evaluate the bond strength and quality of the adhesive interface of bioceramic root canal sealers, 30 single- rooted human teeth will be instrumented using the Reciproc system (R50) with 2.5% NaOCl irrigation. After a final irrigation protocol with 17% EDTA for 5 minutes, followed by final rinsing with saline solution, the specimens will be randomly allocated into 3 experimental groups according to the sealer used (n=10 each): pre-mixed bioceramic sealer BioRoot Flow, and powder-liquid bioceramic sealer BioRoot RCS, compared to AH Plus resin-based sealer. The canals will be dried and obturated using the single-cone technique (R50). After 3 times the setting time of the cements, the specimens will be transversely sectioned into 1 mm (± 0.1 mm) thick slices, obtaining 3 slices from each root third. The first and second slices from each third will be used for push-out testing followed by failure pattern analysis, while the third slice from each third will be used for analysis of the adhesive interface quality by confocal laser microscopy (CLM). Data from the physicochemical properties, bond strength, failure pattern, and adaptation of the adhesive interface of the evaluated cements will be subjected to statistical analysis.